JP4270609B2 - Water-based ink composition - Google Patents

Description

【０００９】
（式中、ｎは自然数を表す。）で示される化合物、及びスチレン−マレイン酸共重合体を含有することを特徴とする。
【００１０】
【発明の実施の形態】
以下、本発明の実施の形態を詳細に説明する。
本発明の水性インキ組成物（以下、単に「インキ」ということもある。）は、水、着色剤、下記一般式（Ｉ）
【００１１】
【化３】

【００１２】
（式中、ｎは自然数を表す。）で示される化合物、及びスチレン−マレイン酸共重合体を含有することを特徴とする。
【００１３】
本発明で用いられる上記一般式（Ｉ）で示される化合物は、一般式（Ｉ）におけるｎの値が異なる２種類以上の化合物の混合物を用いることが好ましく、一般式（Ｉ）で示される化合物のうちｎ＝１及びｎ≧２である化合物の混合物を用いることがより好ましく、一般式（Ｉ）で示される化合物のうちｎ＝１及びｎが２〜５である化合物の混合物を用いることが更に好ましい。
また、上記一般式（Ｉ）で示される化合物は耐乾燥剤として用いられ、水性インキ組成物中に配合しても、描線のにじみ、かすれ等のインキ性能の低下等を招くことがないものである。
【００１４】
一般式（Ｉ）で示される化合物の具体例としては、例えばパラキシリレングリコール〔一般式（Ｉ）において、ｎ＝１のもの。別名テレフタリルアルコール、1,4−ベンゼンジメタノール〕、4,4'−ビス（ヒドロキシメチル）ジベンジルエーテル〔一般式（Ｉ）において、ｎ＝２のもの。ジキシリレングリコール。〕、4,4''−ビス（ヒドロキシメチル）トリベンジルエーテル〔一般式（Ｉ）において、ｎ＝３のもの。トリキシリレングリコール。〕等が挙げられる。
【００１５】
一般式（Ｉ）で示される化合物の使用量としては、水性インキ組成物全量に対して固形分換算で0.01〜10.0重量％、好ましくは0.1〜5.0重量％の範囲から適宜選択される。
使用量が0.01重量％未満では、目的とする良好な耐乾燥性が得られず、10.0重量％を越えると、溶解しづらくなるばかりか、かえってペン先の乾燥が早まってしまうこととなり好ましくない。
また、一般式（Ｉ）で示される化合物のうちｎ＝１及びｎ≧２である化合物の混合物を用いる場合、ｎ≧２である化合物の上記使用量中の含有量としては、該混合物全量に対して20.0重量％以下、好ましくは1.0〜20.0重量％、より好ましくは3.0〜15.0重量％である。
含有量が20.0重量％以下、特に1.0〜20.0重量％の含有量であると、更に耐乾燥性を効率良く最大限に発揮するものとなる。
【００１６】
本発明で用いられる分子内にフェニル基を有するポリマーは、本発明において固着樹脂等として用いられる。また、該ポリマーの本発明のインキ組成物中への添加は、水溶液及び／又は水溶性エマルションとして添加すれば良い。
【００１７】
分子内にフェニル基を有するポリマーとしては、スチレン−マレイン酸共重合体等のスチレン系共重合体等が挙げられ、これらは、エステル化されているものでも、部分エステルでも、或いは酸無水物となっているものでも良い。該分子内にフェニル基を有するポリマーの具体例としては、ＳＭＡ３０００、ＳＭＡ１４４０、ＳＭＡ１７３５２、ＳＭＡ２６２５（以上、アーコケミカル社製）等の商品名のものが挙げられる。これらは夫々単独で用いても二種以上適宜組み合わせて用いても良い。
【００１８】
分子内にフェニル基を有するポリマーの分子量としては、10万以下、好ましくは1000〜10万、より好ましくは1000〜５万、更に好ましくは1000〜２万の範囲から適宜選択される。
分子量が小さすぎると（分子量が1000未満では）、ガラスやプラスチック等の非吸収面への定着性が悪く、分子量が10万を越えると、インキの粘度が高くなりすぎ、インキ塗布時に充分な流量が得られ無く、これは繊維束芯を用いる筆記具に本発明の水性インキ組成物を用いる場合には好ましくないものとなる。
ガラス転移点としては、200℃以下、好ましくは０〜200℃、より好ましくは０〜150℃、更に好ましくは０〜100℃の範囲から適宜選択される。
ガラス転移点が低すぎると（ガラス転移点が０℃未満では）、塗布されたインキの乾燥性が劣り、ガラス転移点が200℃を越えると、塗布されたインキ塗膜が硬くなり、塗膜が脆く、定着性が劣る。
酸価としては、300以下、好ましくは40〜300、より好ましくは40〜250、更に好ましくは40〜200の範囲から適宜選択される。
酸価が小さすぎると（酸価が40未満では）、樹脂に溶解性を与える酸基の量が少なく、樹脂が充分な溶解性を持たず、描線の定着に障害を生じ、酸価が300を越えると、樹脂自体が高い水溶性を有し、塗布されたインキの耐水性が劣る。
【００１９】
本発明で用いられる分子内にフェニル基を有するポリマーの使用量は、水性インキ組成物中に、該水性インキ組成物全量に対して固形分換算で3.0〜20.0重量％含有する量であれば良く、水性インキ組成物全量に対して、0.1〜25重量％、好ましくは0.5〜15重量％の範囲から適宜選択される。
使用量が0.1重量％未満の場合には、ペン先での優れた耐乾燥性が得られず、また、使用量が25重量％を越えた場合には、インキ粘度が上昇し、快適な筆記性が得られにくく、更に、インキの経時安定性にも影響がでてくる。
【００２０】
本発明で用いられる着色剤は、一般に着色剤として用いられるものであれば特に限定されないが、従来水性インキに用いられる染料、顔料等が挙げられる。
【００２１】
染料としては、例えばアイゼンブリムラレッド４ＢＨ、アイゼンブルムラエローＧＣＬＨ〔以上、(株)アイゼン製〕などの直接染料、例えばアイゼンボンソーＲＨ、アイゼンオパールピンクＢＨ、アイゼンオパールブラックＷＨエクストラコンク〔以上、(株)アイゼン製〕、オリエントソルブルブルーＯＢＸ、オリエントソルブルブルーＯＢＢ〔以上、オリエント化学工業(株)製〕などの酸性染料、例えばタートラジン、アシッドレッド、フロキシン〔以上、(株)アイゼン製〕などの食料染料等が挙げられる。
顔料としては、例えばカーボンブラック、酸化チタン、酸化鉄などの無機顔料、例えばフタロシアニン系顔料、アゾ系顔料等の有機顔料、例えば硫化カルシウム等の無機蛍光顔料、有機蛍光顔料等が挙げられる。
これら着色剤は、夫々単独で用いても二種以上適宜組み合わせて用いても良い。
【００２２】
着色剤の使用量としては、水性インキ組成物全量に対して0.1〜25.0重量％、好ましくは0.5〜20重量％の範囲から適宜選択される。
使用量が0.1重量％未満の場合には、色相濃度が低下し、また、25.0重量％を越えた場合には、インキ粘度が増大することがあり、快適な筆記性が得られにくくなる。
【００２３】
顔料を着色剤として用いる場合には、分散剤を使用することが望ましい。分散剤としては、一般に分散剤として用いられるものであれば特に限定されないが、例えばジョンクリルＪ−62、ジョンクリルＪ−450（以上、ジョンソン社製）、ジョリマーＡＴ−210、ジョリマーＳＥＫ−101〔以上、日本純薬工業(株)製〕などの水溶性樹脂や、アニオン界面活性剤、ノニオン界面活性剤、カチオン界面活性剤、非イオン界面活性剤などの界面活性剤等が挙げられ、これらは夫々単独で用いても二種以上適宜組み合わせて用いても良い。
【００２４】
本発明の水性インキ組成物において、ペン先や被筆記面に対するインキの濡れ性を良好にするために、表面張力調整剤を用いても良い。表面張力調整剤としては、例えばサーフィノール82、サーフィノール61、フロラードＦＣ−95、フロラードＦＣ−176などの界面活性剤等が挙げられ、これらは夫々単独で用いても二種以上適宜組み合わせて用いても良い。
【００２５】
本発明の水性インキ組成物には、また、その必要に応じて有機溶剤を含有させても良い。有機溶剤としては、例えばエチレングリコール、ジエチレングリコール、プロピレングリコール、ジプロピレングリコール、トリメチレングリコール、グリセリン、２−プロパノール等のアルコール類等が挙げられ、これらは夫々単独で用いても二種以上適宜組み合わせて用いても良い。
【００２６】
本発明の水性インキ組成物には、必要に応じて該水性インキ組成物の性質を損なわない範囲で上記以外の成分を含有させても良い。含有可能な成分としては、例えば安息香酸ナトリウム〔和光純薬工業(株)製〕、バイオデン−１８、アモルデン−ＨＳ、アモルデンＢＴ−50、アモルデンＦＳ−14Ｄ〔以上、大和化学工業(株)製〕、プロキセルＢＤＮ、プロキセルＧＸＬ、プロキセルＴＮ、〔以上、ゼネカ(株)製〕などの防菌剤、例えばアンモニア、アミノメチルプロパノール、トリエタノールアミン〔以上、和光純薬工業(株)製〕などのｐＨ調整剤等が挙げられる。更に本発明の水性インキ組成物をボールペンインキとして用いた場合には、防蝕剤（防虫剤）、潤
滑剤、防腐剤、防錆剤、消泡剤、カスレ防止剤等を用いてもよい。
【００２７】
本発明の水性インキ組成物は、例えば下記のような方法により製造することができる。
先ず、着色剤として染料を用いる場合には、上記成分を撹拌混合して溶解させる。また、着色剤として顔料又は顔料と染料とを併用する場合には、上記成分を公知の分散機、例えばボールミル、ロールミル、サンドミル、フローミル、ダイノーミル、アトライタ等で混合粉砕を行う。
次に、撹拌混合又は混合粉砕して得られた中間物を、必要に応じて濾過、遠心沈降等の方法で粗大粒子やゴミを除去することにより容易に目的の水性インキ組成物を得ることができる。
【００２８】
本発明の水性インキ組成物は、例えばボールペン、マーキングペン等の筆記具、浸透印、スタンプ台、記録装置やプリンター等の印刷装置等に用いることができる。
【００２９】
本究明の水性インキ組成物が、耐乾燥性に優れ、かつ非吸収面への固着性、経時安定性等に優れている理由としては、以下のように推察される。
即ち、本発明の水性インキ組成物を充填したペン体をキャップオフの状態で放置すると、ペン先より水分が蒸発し、ペン先先端部のインキの固形分濃度が上昇し、上記一般式（Ｉ）で示される化合物の結晶がインキの気−液界面に容易に析出しペン先からのインキの蒸発を抑制または停止させる。しかしながら、前記化合物は、常温で粗い結晶であるために筆記描線の堅牢性が損なわれ、水に対する溶解状態が不安定であるためにインキ自体の安定性も損なわれる可能性があった。このようなインキ中に、分子内にフェニル基を有するポリマーを配合することによって、前記化合物が該ポリマー中の一部に可溶化され、従来筆記描線中で遊離（結晶化）していた前記化合物が減少し筆記描線の堅牢性が向上、インキ中の溶解状態も安定すると考えられる。
【００３０】
【実施例】
以下に、実施例、比較例及び試験例等を挙げて本発明を更に詳細に説明するが、本発明は実施例によって何ら限定されるものではない。
【００３２】
実施例１．
下記成分を混合粉砕した後、濾過することにより青色インキを得た。
水 ６４．４８重量部
Ｅｍａｃｏｌ． Ｂｌｕｅ． ＦＢ〔三洋色素（株）製〕 １８．００重量部
ジョンクリルＪ−４５０ １１．１３重量部
トリエタノールアミン ０．１３重量部
プロキセルＢＤＮ ０．２３重量部
ＳＭＡ３０００ ３．００重量部
（スチレン−マレイン酸共重合体：固着樹脂。固形分：１００％）
（重量平均分子量：１９００、ガラス転移点：１１５〜１３０℃、酸価：２７５）
フロラードＦＣ−９５ ０．０３重量部
パラキシリレングリコール ２．８２重量部
４，４’−ビス（ヒドロキシメチル）ジベンジルエーテル ０．１８重量部
【００３３】
実施例２．
下記成分を混合粉砕した後、濾過することにより赤色インキを得た。
水 ５２．０１重量部
Ｆｕｊｉ． ＳＰ． Ｒｅｄ． ５１１１〔富士色素（株）製〕 １８．００重量部
ジョリマーＡＴ２１０ １２．００重量部
プロピレングリコール １０．００重量部
アミノメチルプロパノール ０．１３重量部
アモルデン−ＨＳ ０．２０重量部
ＳＭＡ１７３５２ ３．００重量部
（スチレン−マレイン酸共重合体：固着樹脂。固形分：１００％）
（重量平均分子量：１７００、ガラス転移点：１６０〜１７０℃、酸価：２７０）
２−プロパノール １．００重量部
２５％アンモニア水 ０．５６重量部
サーフィノール６１ ０．１０重量部
パラキシリレングリコール ２．８５重量部
４，４’−ビス（ヒドロキシメチル）ジベンジルエーテル ０．１５重量部
【００３４】
実施例３．
下記成分を混合撹拌した後、濾過することにより赤色インキを得た。
水 ５４．６７重量部
アイゼンブリムラレッド４ＢＨ ３．７７重量部
アイゼンブルムラエローＧＣＬＨ ０．２３重量部
プロピレングリコール ３０．００重量部
トリエタノールアミン ０．０１重量部
安息香酸ナトリウム １．２２重量部
ＳＭＡ１４４０ ７．００重量部
（スチレン−マレイン酸共重合体：固着樹脂。固形分：１００％）
（重量平均分子量：２５００、ガラス転移点：５５〜７５℃、酸価：１８５）
サーフィノール８２ ０．１０重量部
パラキシリレングリコール ２．８２重量部
４，４’−ビス（ヒドロキシメチル）ジベンジルエーテル ０．１８重量部
【００３９】
比較例１．
下記成分を混合粉砕した後、濾過することにより黒色インキを得た。

【００４０】
比較例２．
下記成分を混合粉砕した後、濾過することにより青色インキを得た。

【００４１】
比較例３
下記成分を混合粉砕した後、濾過することにより赤色インキを得た。

【００４２】
比較例４．
下記成分を混合撹拌した後、濾過することにより赤色インキを得た。

【００４３】
比較例５．
下記成分を混合粉砕した後、濾過することにより黒色インキを得た。

【００４４】
比較例６．
下記成分を混合粉砕した後、濾過することにより青色インキを得た。

【００４５】
比較例７．
下記成分を混合粉砕した後、濾過することにより赤色インキを得た。

【００４６】
比較例８．
下記成分を混合撹拌した後、濾過することにより赤色インキを得た。

【００４７】
試験例１．実施例１〜３及び比較例１〜８で得られたインキを細書用水性ペン〔三菱ＰＩＮ−１０３：三菱鉛筆（株）製〕に充填し、得られたペンの品質の経時安定性（ノンドライ性評価）及び非吸収面での固着性（固着性評価）について下記評価試験を行った。結果を下記表１に示す。
【００４８】
（１）ノンドライ性評価試験
上記のようにして得られたペンについて、▲１▼作製直後のもの、▲２▼５０℃で２日間経時保管したもの、及び▲３▼−１０℃で２日間経時保管したものを夫々、先ず「三菱鉛筆」と筆記し、２５℃、湿度６５％の環境下で１時間キャップを開放したまま放置した。放置後、再び「三菱鉛筆」と２回筆記して、筆記の可否について評価を行った。尚、評価基準は以下の通りである。
・評価基準
◎：最初から筆記できる。
〇：１回目の「三」の字を書いている途中から復帰した。
□：１回目の「菱」の字を書いている途中から復帰した。
△：１回目の「鉛筆」を書いている途中から復帰した。
●：２回目の「三菱鉛筆」を書いている途中から復帰した。
×：「三菱鉛筆」を２回書いているうちには復帰しなかった。
【００４９】
（２）固着性評価試験
上記のようにして得られたペンを非吸収面（ＰＥＴフィルム及びガラス板）に螺旋５周を筆記し、乾燥後、描線を指先の指紋で１０回同じ方向に擦過し、擦過後の描線について評価を行った。尚、評価基準は以下の通りである。
・評価基準
◎：擦過前と同じ（全く消えていない）。
〇：描線の２５％が消去。
□：描線の５０％が消去。
△：描線の７５％が消去。
×：描線が全て消去。
【００５０】
【表１】

【００５１】
（表１の考察）
表１の結果からも明らかなように、実施例１〜３で得られた本発明のインキは、比較例１〜８で得られたインキに比べ、非吸収面への固着性に優れ、また、−１０℃の低温及び５０℃の高温での品質の経時安定性も優れていることが判る。このことからも本発明の水性インキ組成物が明らかに優れていることが判る。
【００５２】
【発明の効果】
以上のように、本発明の水性インキ組成物は、筆記具のペン先における耐乾燥性に優れ、非吸収面での良好な固着性、低温及び高温での良好な品質の経時安定性等を有する、という点に顕著な効果を奏するものである。また、上記一般式（Ｉ）で示される化合物とスチレン−マレイン酸共重合体とを組み合わせて用いた本発明の水性インキ組成物は、上記したような効果や筆記時の描線のにじみ、かすれ等について更に向上したばかりでなく、強い擦過等の力に対しての描線強度が向上し、上記一般式（Ｉ）で示される化合物の溶解状態の安定性が増したと考えられ、そのため、−１０℃以下の低温または３０℃以上の高温での物性の安定性が更に増加した、という点に相乗的な効果を奏するものである。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a water-based ink composition excellent in drying resistance, stability over time, adhesion on a non-absorbing surface, and the like that can be used for writing instruments, stamps, recorders, printers, printing, and the like.
[0002]
[Prior art]
Writing tools that use water-based ink so far cannot be written if the cap is removed from the writing tool body and the nib is exposed to the atmosphere for a long period of time. There was a case.
[0003]
Therefore, in order to obtain a water-based ink excellent in drying resistance, an ink in which a water-soluble organic solvent such as ethylene glycol or urea is added is known.
However, if water-soluble organic solvents such as ethylene glycol and propylene glycol and urea are used in the composition in order to make water-based inks excellent in drying resistance, they must be added in a considerably large amount. As a result, satisfactory performance improvement was not recognized. In such a case, there are problems such as difficulty in flowing out due to an increase in ink viscosity, blurring of drawn lines, and marked decrease in drawn line adhesion on the non-absorbing surface after writing due to difficulty in drying the ink. It was. In addition, when a water-soluble organic solvent such as ethylene glycol is used in the ink, the surface tension of the ink is lowered, and the drawn line is liable to be blurred, so that a clear drawn line cannot be obtained. Further, when urea is added to the ink, the urea is decomposed when the ink is stored at a high temperature, and there is a problem in its stability. Furthermore, when these additives as described above are added to the ink composition in order to improve the drying resistance, the ink performance is often lowered.
[0004]
On the other hand, water-based inks containing paraxylylene glycols, when filled into a pen body, have good resistance to dryness at the tip of the pen and have few drawbacks such as blurring and blurring during writing. Compared to the case where a water-soluble organic solvent such as glycol or glycerin is used, it has an effect that the drawn line stickiness on the non-absorbing surface is good.
However, due to recent market needs and the like, there is a situation where further improvement is desired with respect to the effects described above, the drawn line strength, and the stability of physical properties at a low temperature of 10 ° C. or lower or a high temperature of 30 ° C. or higher.
Also known are those obtained by adding a water-soluble copolymer or water-soluble emulsion having a phenyl group in the molecule to an ink composition (Japanese Patent Laid-Open Nos. 5-30413, 6-228486, and 6). -228487).
However, although such an ink composition can obtain a certain degree of drawing strength, the ink is not “applied” on the non-absorbing surface and the paper surface subjected to some surface treatment, and sufficient drawing strength is also obtained. There was a problem that it could not be obtained.
[0005]
[Problems to be solved by the invention]
The present invention has been made in view of the above-described conventional problems. There is no blurring or blurring of drawn lines, no deterioration or change in ink performance, drying resistance, stability over time, adhesion to a non-absorbing surface. It aims at providing the water-based ink composition excellent in property etc.
[0006]
[Means for Solving the Problems]
As a result of intensive studies in order to solve the above problems, the present inventors have added the compound represented by the general formula (I) and a polymer having a phenyl group in the molecule to the above-mentioned conventional one. Thus, the present invention has been completed by finding a water-based ink composition having good drying resistance, stability over time, and good adhesion to drawn lines on a non-absorbing surface.
[0007]
That is, the water-based ink composition of the present invention comprises water, a colorant, the following general formula (I)
[0008]
[Chemical formula 2]

[0009]
(Wherein n represents a natural number) and a styrene-maleic acid copolymer .
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail.
The water-based ink composition of the present invention (hereinafter sometimes simply referred to as “ink”) includes water, a colorant, the following general formula (I):
[0011]
[Chemical 3]

[0012]
(Wherein n represents a natural number) and a styrene-maleic acid copolymer .
[0013]
The compound represented by the general formula (I) used in the present invention is preferably a mixture of two or more compounds having different values of n in the general formula (I), and the compound represented by the general formula (I) Among them, it is more preferable to use a mixture of compounds where n = 1 and n ≧ 2, and among compounds represented by the general formula (I), a mixture of compounds where n = 1 and n is 2 to 5 is used. Further preferred.
Further, the compound represented by the general formula (I) is used as a desiccant, and even when blended in a water-based ink composition, it does not cause deterioration of ink performance such as blurring of drawn lines and blurring. is there.
[0014]
Specific examples of the compound represented by the general formula (I) include, for example, paraxylylene glycol [in the general formula (I), n = 1. Also known as terephthalyl alcohol, 1,4-benzenedimethanol, 4,4'-bis (hydroxymethyl) dibenzyl ether [in formula (I), n = 2. Dixylylene glycol. ], 4,4 ''-bis (hydroxymethyl) tribenzyl ether [in formula (I), n = 3. Trixylylene glycol. ] Etc. are mentioned.
[0015]
The amount of the compound represented by the general formula (I) is appropriately selected from the range of 0.01 to 10.0% by weight, preferably 0.1 to 5.0% by weight in terms of solid content with respect to the total amount of the water-based ink composition.
If the amount used is less than 0.01% by weight, the desired good drying resistance cannot be obtained, and if it exceeds 10.0% by weight, it is not only difficult to dissolve, but also the pen tip is undesirably dried.
Moreover, when using the mixture of the compound which is n = 1 and n> = 2 among the compounds shown by general formula (I), as content in the said usage-amount of the compound which is n> = 2, it is in this mixture whole quantity. It is 20.0 weight% or less with respect to it, Preferably it is 1.0-20.0 weight%, More preferably, it is 3.0-15.0 weight%.
When the content is 20.0% by weight or less, particularly 1.0 to 20.0% by weight, the drying resistance is further efficiently and maximized.
[0016]
The polymer having a phenyl group in the molecule used in the present invention is used as a fixing resin or the like in the present invention. The polymer may be added to the ink composition of the present invention as an aqueous solution and / or a water-soluble emulsion.
[0017]
The polymer having a phenyl group in the molecule, scan styrene - styrene copolymer and maleic acid copolymer and the like, which may be those that have been esterified, in partial esters, or acid anhydrides It may be what is. Specific examples of the polymer having a phenyl group in the molecule, S MA3000, SMA1440, SMA17352, SMA2625 ( or, Arco Chemical Co.) include the trade names such as. These may be used alone or in appropriate combination of two or more.
[0018]
The molecular weight of the polymer having a phenyl group in the molecule is appropriately selected from the range of 100,000 or less, preferably 1,000 to 100,000, more preferably 1,000 to 50,000, and still more preferably 1,000 to 20,000.
If the molecular weight is too small (if the molecular weight is less than 1000), the fixability to non-absorbing surfaces such as glass and plastic is poor. If the molecular weight exceeds 100,000, the viscosity of the ink becomes too high, and the flow rate is sufficient for ink application. This is not preferable when the water-based ink composition of the present invention is used for a writing instrument using a fiber bundle core.
The glass transition point is appropriately selected from the range of 200 ° C. or lower, preferably 0 to 200 ° C., more preferably 0 to 150 ° C., and still more preferably 0 to 100 ° C.
If the glass transition point is too low (if the glass transition point is less than 0 ° C), the drying property of the applied ink is inferior. If the glass transition point exceeds 200 ° C, the applied ink coating becomes hard, and the coating film Is brittle and inferior in fixability.
The acid value is appropriately selected from the range of 300 or less, preferably 40 to 300, more preferably 40 to 250, and still more preferably 40 to 200.
If the acid value is too small (if the acid value is less than 40), the amount of acid groups that give solubility to the resin is small, the resin does not have sufficient solubility, and the fixing of drawn lines is hindered, and the acid value is 300 If it exceeds, the resin itself has high water solubility, and the applied ink has poor water resistance.
[0019]
The amount of the polymer having a phenyl group in the molecule used in the present invention may be an amount contained in the water-based ink composition in an amount of 3.0 to 20.0% by weight in terms of solid content with respect to the total amount of the water-based ink composition. The content is appropriately selected from the range of 0.1 to 25% by weight, preferably 0.5 to 15% by weight, based on the total amount of the water-based ink composition.
When the amount used is less than 0.1% by weight, excellent drying resistance at the pen tip cannot be obtained, and when the amount used exceeds 25% by weight, the ink viscosity increases and the writing is comfortable. It is difficult to obtain the properties, and the stability of the ink over time is also affected.
[0020]
The colorant used in the present invention is not particularly limited as long as it is generally used as a colorant, and examples thereof include dyes and pigments conventionally used in water-based inks.
[0021]
Examples of the dye include direct dyes such as Eisen Burimura Red 4BH and Eisenbulla Yellow GCLH [above, manufactured by Eisen Co., Ltd.], such as Eisenbonso RH, Eisen Opal Pink BH, Eisen Opal Black WH Extra Conc. Acid Dye], Orient Soluble Blue OBX, Orient Soluble Blue OBB [above, manufactured by Orient Chemical Co., Ltd.], for example, Tartrazine, Acid Red, Phloxin [above, Eisen Co., Ltd.] And food dyes.
Examples of the pigment include inorganic pigments such as carbon black, titanium oxide and iron oxide, organic pigments such as phthalocyanine pigments and azo pigments, inorganic fluorescent pigments such as calcium sulfide, and organic fluorescent pigments.
These colorants may be used alone or in appropriate combination of two or more.
[0022]
The amount of the colorant used is appropriately selected from the range of 0.1 to 25.0% by weight, preferably 0.5 to 20% by weight, based on the total amount of the water-based ink composition.
When the amount used is less than 0.1% by weight, the hue density decreases, and when it exceeds 25.0% by weight, the ink viscosity may increase, making it difficult to obtain comfortable writing properties.
[0023]
When using a pigment as a colorant, it is desirable to use a dispersant. The dispersant is not particularly limited as long as it is generally used as a dispersant. For example, John Crill J-62, John Crill J-450 (above, manufactured by Johnson), Jolimer AT-210, Jolimer SEK-101 [ As mentioned above, water-soluble resins such as Nippon Pure Chemical Industries Ltd., and surfactants such as anionic surfactants, nonionic surfactants, cationic surfactants, nonionic surfactants, etc. Each may be used alone or in combination of two or more.
[0024]
In the water-based ink composition of the present invention, a surface tension adjusting agent may be used in order to improve the wettability of the ink with respect to the pen tip or the writing surface. Examples of the surface tension adjusting agent include surfactants such as Surfinol 82, Surfinol 61, Fluorard FC-95, and Fluorard FC-176. These may be used alone or in combination of two or more. May be.
[0025]
The water-based ink composition of the present invention may contain an organic solvent as necessary. Examples of the organic solvent include alcohols such as ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, trimethylene glycol, glycerin, and 2-propanol. These may be used alone or in combination of two or more. It may be used.
[0026]
The water-based ink composition of the present invention may contain components other than those described above as long as they do not impair the properties of the water-based ink composition. Examples of components that can be contained include sodium benzoate (manufactured by Wako Pure Chemical Industries, Ltd.), Bioden-18, Amorden-HS, Amorden BT-50, and Amorden FS-14D (manufactured by Daiwa Chemical Industry Co., Ltd.). PH of antibacterial agents such as Proxel BDN, Proxel GXL, Proxel TN, [made by Zeneca Co., Ltd.], such as ammonia, aminomethyl propanol, triethanolamine [made by Wako Pure Chemical Industries, Ltd.] Examples include regulators. Furthermore, when the water-based ink composition of the present invention is used as a ballpoint pen ink, a corrosion inhibitor (insect repellent), a lubricant, an antiseptic, a rust inhibitor, an antifoaming agent, an anti-scratch agent, and the like may be used.
[0027]
The water-based ink composition of the present invention can be produced, for example, by the following method.
First, when a dye is used as a colorant, the above components are mixed by stirring and dissolved. When a pigment or a pigment and a dye are used in combination as a colorant, the above components are mixed and pulverized with a known disperser such as a ball mill, roll mill, sand mill, flow mill, dyno mill, or attritor.
Next, the intermediate product obtained by stirring and mixing or mixing and pulverizing can easily obtain the desired aqueous ink composition by removing coarse particles and dust by a method such as filtration and centrifugal sedimentation, if necessary. it can.
[0028]
The water-based ink composition of the present invention can be used, for example, in writing instruments such as ballpoint pens and marking pens, penetrating marks, stamp stands, printing apparatuses such as recording apparatuses and printers, and the like.
[0029]
The reason why the water-based ink composition of the present study is excellent in drying resistance, and is excellent in adhesion to a non-absorbing surface, stability over time, etc. is presumed as follows.
That is, when the pen body filled with the water-based ink composition of the present invention is left in a cap-off state, water is evaporated from the pen tip, the solid content concentration of the ink at the tip of the pen tip is increased, and the general formula (I ) Easily precipitates at the gas-liquid interface of the ink and suppresses or stops the evaporation of the ink from the nib. However, since the compound is a coarse crystal at normal temperature, the fastness of writing lines is impaired, and since the water-soluble state is unstable, the stability of the ink itself may be impaired. In such an ink, by blending a polymer having a phenyl group in the molecule, the compound is solubilized in a part of the polymer and is conventionally freed (crystallized) in a writing line. It is considered that the fastness of writing lines is improved and the dissolved state in ink is stable.
[0030]
【Example】
Hereinafter, the present invention will be described in more detail with reference to examples, comparative examples, and test examples, but the present invention is not limited to the examples.
[0032]
Example 1 .
The following components were mixed and ground and then filtered to obtain a blue ink.
64.48 parts by weight of water Emacol. Blue. FB [manufactured by Sanyo Color Co., Ltd.] 18.00 parts by weight Jonkrill J-450 11.13 parts by weight Triethanolamine 0.13 parts by weight Proxel BDN 0.23 parts by weight SMA3000 3.00 parts by weight (styrene-maleic acid Copolymer: fixing resin, solid content: 100%)
(Weight average molecular weight: 1900, glass transition point: 115-130 ° C., acid value: 275)
Fluorad FC-95 0.03 parts by weight Paraxylylene glycol 2.82 parts by weight 4,4′-bis (hydroxymethyl) dibenzyl ether 0.18 parts by weight
Example 2 .
The following components were mixed and ground and then filtered to obtain a red ink.
Water 52.01 parts by weight Fuji. SP. Red. 5111 [Fuji Dye Co., Ltd.] 18.00 parts by weight Jolimer AT210 12.00 parts by weight Propylene glycol 10.00 parts by weight Aminomethylpropanol 0.13 parts by weight Amorden-HS 0.20 parts by weight SMA17352 3.00 parts by weight (Styrene-maleic acid copolymer: fixing resin, solid content: 100%)
(Weight average molecular weight: 1700, glass transition point: 160-170 ° C., acid value: 270)
2-propanol 1.00 parts by weight 25% aqueous ammonia 0.56 parts by weight Surfynol 61 0.10 parts by weight Paraxylylene glycol 2.85 parts by weight 4,4′-bis (hydroxymethyl) dibenzyl ether 0.15 Weight part 【0034】
Example 3 .
The following components were mixed and stirred and then filtered to obtain a red ink.
Water 54.67 parts by weight Eisen muramura red 4BH 3.77 parts by weight Eisen murara yellow GCLH 0.23 parts by weight Propylene glycol 30.00 parts by weight Triethanolamine 0.01 parts by weight Sodium benzoate 1.22 parts by weight SMA 1440 7.00 parts by weight (styrene-maleic acid copolymer: fixing resin, solid content: 100%)
(Weight average molecular weight: 2500, glass transition point: 55 to 75 ° C., acid value: 185)
Surfynol 82 0.10 parts by weight Paraxylylene glycol 2.82 parts by weight 4,4′-bis (hydroxymethyl) dibenzyl ether 0.18 parts by weight
Comparative Example 1
The following components were mixed and pulverized, and then filtered to obtain a black ink.

[0040]
Comparative Example 2
The following components were mixed and ground and then filtered to obtain a blue ink.

[0041]
Comparative Example 3
The following components were mixed and ground and then filtered to obtain a red ink.

[0042]
Comparative Example 4
The following components were mixed and stirred and then filtered to obtain a red ink.

[0043]
Comparative Example 5
The following components were mixed and pulverized, and then filtered to obtain a black ink.

[0044]
Comparative Example 6
The following components were mixed and ground and then filtered to obtain a blue ink.

[0045]
Comparative Example 7
The following components were mixed and ground and then filtered to obtain a red ink.

[0046]
Comparative Example 8
The following components were mixed and stirred and then filtered to obtain a red ink.

[0047]
Test Example 1 The inks obtained in Examples 1 to 3 and Comparative Examples 1 to 8 were filled into a water-based pen for fine writing [Mitsubishi PIN-103: manufactured by Mitsubishi Pencil Co., Ltd.], and the quality of the resulting pen over time (non-dry) The following evaluation tests were conducted on the adhesiveness evaluation) and on the non-absorbing surface adhesiveness (adhesiveness evaluation). The results are shown in Table 1 below.
[0048]
(1) Non-drying evaluation test About the pen obtained as described above, (1) immediately after preparation, (2) stored for two days at 50 ° C., and (3) for two days at −10 ° C. Each of the stored items was first written as “Mitsubishi Pencil” and left in an environment of 25 ° C. and 65% humidity for 1 hour with the cap open. After leaving it alone, it was written twice as “Mitsubishi Pencil” again to evaluate whether writing was possible. The evaluation criteria are as follows.
・ Evaluation criteria ◎: Can be written from the beginning.
〇: Returned from the middle of writing the first “three” character.
□ Returned from the middle of writing the first letter of “Hishi”.
Δ: Returned from the middle of writing the first “pencil”.
●: Returned from the middle of writing the second “Mitsubishi Pencil”.
X: It did not return while writing "Mitsubishi Pencil" twice.
[0049]
(2) Adhesion evaluation test The pen obtained as described above was written on the non-absorbing surface (PET film and glass plate) with 5 turns of the spiral, and after drying, the drawn line was rubbed 10 times with the fingerprint of the fingertip in the same direction. Then, the drawn lines after rubbing were evaluated. The evaluation criteria are as follows.
-Evaluation criteria A: Same as before rubbing (not disappeared at all).
○: 25% of the drawn lines are erased.
□: 50% of the drawn lines are erased.
Δ: 75% of drawn lines are erased.
X: All drawn lines are erased.
[0050]
[Table 1]

[0051]
(Consideration of Table 1)
As is clear from the results in Table 1, the inks of the present invention obtained in Examples 1 to 3 are excellent in adhesion to the non-absorbing surface compared to the inks obtained in Comparative Examples 1 to 8, and It can be seen that the temporal stability of the quality at a low temperature of −10 ° C. and a high temperature of 50 ° C. is also excellent. This also shows that the water-based ink composition of the present invention is clearly superior.
[0052]
【The invention's effect】
As described above, the water-based ink composition of the present invention is excellent in drying resistance at the pen tip of a writing instrument, has good adhesion on a non-absorbing surface, and good quality stability over time at low and high temperatures. , Has a remarkable effect. In addition, the water-based ink composition of the present invention using a combination of the compound represented by the general formula (I) and the styrene-maleic acid copolymer has the above-described effects, blurring of drawn lines at the time of writing, blurring, etc. It is considered that the strength of the drawn line against the force of strong rubbing and the like was improved and the stability of the dissolved state of the compound represented by the general formula (I) was increased. This has a synergistic effect in that the stability of physical properties at the following low temperature or at a high temperature of 30 ° C. or higher is further increased.

Claims (6)

Water, colorant, the following general formula (I)

A water-based ink composition comprising a compound represented by the formula (wherein n represents a natural number) and a styrene-maleic acid copolymer .   The water-based ink composition according to claim 1, wherein the compound represented by the general formula (I) is a mixture of two or more compounds having different values of n in the general formula (I).   The compound represented by the general formula (I) is a mixture of compounds represented by the general formula (I) where n = 1 and n ≧ 2, and the polymer having a phenyl group in the molecule has a molecular weight of 1000. The water-based ink composition according to claim 1, which has a glass transition point of 0 to 200 ° C. and an acid value of 40 to 300.   The water-based ink composition according to any one of claims 1 to 3, wherein a polymer having a phenyl group in the molecule is blended in an aqueous solution or a water-soluble emulsion.   The compound represented by the general formula (I) in the water-based ink composition is 0.01 to 10.0% by weight in terms of solid content, and the polymer having a phenyl group in the molecule is 3.0 to 20 in terms of solid content. The water-based ink composition according to any one of claims 1 to 4, comprising 0.0% by weight.   4. The mixture of compounds represented by formula (I) wherein n = 1 and n ≧ 2 contains 1.0 to 20.0% by weight of the compound where n ≧ 2 in the mixture. Or the water-based ink composition of 5.